Technical Manual TM 9-782 TRACTOR, LIGHT, WHEELED INDUSTRIAL TYPE (A-C MODEL B) 1942 The light tractor, M2, Allis-Chalmers, model B, is a four-wheeled industrial type tractor. It is powered with a heavy-duty, four-cylinder, water-cooled, gasoline engine. Steering is accomplished with an automobile type steering wheel. There are three forward speeds and one reverse speed provided to accommodate different loads.